I have not used it yet, but here are my 2 cents ...
The pip has something to do with guicyol that I don't really understand. Some DHB oils have less and some more pip. In any case from what I've read it's tren's little baby brother, without the tren sides - but with standard, albeit a bit stronger, DHT sides. When injecting it, it's smart to mix it with another oil, usually test, that has no pip and also, keep the oil volume as low as possible. Thus it might be better to take more small weekly injections compared to 1 or 2 larger ones. I would also be very careful for DHB not to creep up into the subQ area, as that could lead to even more pain and complications. So a deeper injection into the muscle would be my recommendation. And you probably don't need a lot of it, 400 mg's would be the most I would use (alongside some test off course).